Spring attachment for governors



(No Model.)

0. M. GIDDINGS.

SPRING ATTACHMENT FOR GOVERNORS.

No. 391,239. Patented Oct. 16, 1888.

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' attachment,illustrating myimprovement; and

UNTTnb STATES PATENT OFFICE,

GHAlt'fil lS ill. GIDDINGS,OF MASSILLON, OHIO.

SPRING ATTACHMENT FOR GOVERNORS.

SPECIFICATION forming part of Letters Patent No. 391,239. dated October 16, 1888.

Application filedMay17,iRSS. Serial Xe. 371.1 12. (No model.)

To all whom, it may concern.-

Be it known that l, CHARLES M. (lrnnmcs, of Massillon, Stark county Ohio, have invented certain new and useful Improvements in Spring Attachments for Governors, of which the following is a specification.

This invention pertains to that class of governors employed in connection with steam and other engines in which centrifugally-acting levers centripetally resisted by springs serve in effecting the adjustment of the eccentric or other element of steam control. In this class of governors spiral springs are generally employed to furnish the centripetal force. There is a theoretical law relating to the action of spiral springs, which is that the tension of the spring increases with the extension of length of the spring if the spring acts tensionally, and with the contraction of length of the spring if the spring acts compressively. According to thislaw a spiral spring in which ten pounds caused an extension of length of one inch should be extended two inches by a force of twenty pounds. in practice the law is not to be depended upon, as it is often found that in a lot of apparently similar springs one spring may follow the law, while another spring in creases its tension per unit of extension,while still another spring may have a decreasing ten sion per unit of extension.

My improvement relates to a spring attachment by means of which a spring having a uniform tension per unit of extension may apply its force upon uniform leverage, while a spring increasing its force per unit of extension may be adjusted to act upon a decreasing leverage, and a spring decreasing its force upon an increasing leverage.

My improvement will be readily understood from the following description, taken in connection with the accompanying drawings, in which- Figure 1 is a perspective View of a spring Fig. 2, a face view of an ordinary steam-engine governor of the shaft or disk type provided with my improvement.

In the drawings, A indicates the usual centrifugal weights; B, the usual pivot-levers carrying these weights and serving, in the usual manner, by their movement under centrifugal action of the weights to effect the control of motor speed; 0, the pivots on which the levers B oscillate; D, the usual centripetal spring acting inwardly upon the levers and serving to resist the centrifugal action of the weights; E, the pivot-eyes of the lovers; F, a sectorblock upon each lever B, the axis of the arc of the sector coinciding normally wit-h the axis of its leverpivot, the radius of the arc of the sector being such that the axis of its spring D is substantially tangent to the are; G, a square pivot disposed across each sector-block and engaging a notch in its appropriatelever, this square pivot forminga knife-edge pivot of engagement between sector-block and lever; H, the peripheral surfaces of the sector block; J, a flexible connection (shown in the illustration as of wire rope) connecting a sector-block with its appropriate spring this flexible connection being attached at one end to the spring and at the other end to the sector-block, the intermediate portions of the flexible connection engaging more or less of the peripheral surface of the sector-block as the lever carrying the sector-block vibrates; K, an adj ustingscrew engaging the pivot-eye of the lever B, and also the sector-block, and serving as a means by which the relation of the are of the sector-block may be adjusted with reference to the lever; L, slots in lugs projecting radially from the arc of the sector-block, and M the ends' of the flexible connection secured to the sectorblock at these slots.

In the absence of the screws K the sectorblock would be at liberty to rock freely with reference to the lever upon its knife-edge hearing. The presence of the screw K prevents such oscillation in one direction, and the strain of the spring through its flexible connection serves in keeping the sectorblock always against that screw, so that the sector-block during the working of the governor becomes virtually a rigid part of the lever to which it is attached.

Assuming that the arc of the sector is concentric with the pivot G of its lever, it follows that as the lever-l3 vibrates in working, the flexible connection H will always engage the periphery of the sector at the same distance from the pivot 0, whereby the spring is caused to act upon the lever and weight with a uniform leverage. Therefore if the spring be a spring whose rate of tension is uniform per unit of extension, the spring will exercise a uniform rate of force per unit of movement of lever. If, however, the spring should prove to havea decreasing tension per unit of extension, then in order to effect a compensation it is desirable to provide that the effective leverage upon which the spring acts shall increase as the spring becomes extended. This is accomplished in the device by adjusting the screw K to move the toe of the sector away from the pivot 0, thus bringing the arc of the sector eccentric to the pivot. Then as the lever vibrates and the spring becomes extended the leverage on which the spring acts will become increased. If the spring should be found to increase its tension per unit of extension, then the sector will be adjusted in the other direction, so that thelever on which the spring acts decreases as the spring extends.

The sectorblock illustrated is slotted to straddle its lever B, the square pivot G being passed through the jaws of the slot over the lever. The wire rope J has its ends M enlarged, as by solder or otherwise, and both these enlarged ends seat in appropriate holes in the projecting lugs of the sector, the wire rope thus forming a swing straddling the lever and engaging with its intermediate portion an appropriate eye at the end of the spring, the face of thelug L having slots open into the holes engaged by the ends of the rope, so that the ends of the rope can be pushed inwardly and then withdrawn sidewise from the slots, and the slots are arranged somewhat diagonally to the line of the rope, as clearly shown in the drawings, so that an outward bend. is given to the ends of the rope, thus causing a biting impingement of the rope ends in their seats, thus serving as a cramp to aid in securing the rope ends to their places, and serving also as a means for carrying the ropes swung between the spring and lever.

I claim as my invention- 1. The combination, substantially as set forth,with a pivoted weighted lever and a centripetal spring, of a sector-block mounted on the lever and a flexible connection uniting the spring to. the lever and engaging the periphery of the sector-block.

2. The combination, substantially as set forth, with a pivoted weighted lever and a centripetal spring, of a sector-block pivoted to the lever, a screw adapted to adjust the sector-block upon its pivot with reference to the pivot of the lever, and a flexible connection uniting the spring to the lever and engaging the periphery of the sector-block.

3. The combination, substantially as set forth,with the pivoted lever B, weight A, and centripetal spring D, of sector-block F, pivot G, screw K, and flexible connection J.

c. M. GIDDINGS.

\Vitnesses:

J OHN W. SNooK, T. D. VAN DUYN. 

